Thirty years after a boycott of Nestlé products was launched to highlight its unethical marketing of baby formula in developing countries, baby formula manufacturers are still failing in their responsibilities towards the world's poorest mothers and babies, Save the Children claims today.

It says around 1.4 million children die each year of illnesses such as diarrhoea that could have been prevented if they were being breastfed. But - despite the dangers of mixing infant formula with dirty water and using unsterile bottles - food companies continue to use aggressive marketing techniques to keep their share of a multi-million pound market.

Since 1981, baby milk manufacturers have been bound by a World Health Organisation-ratified code which bans direct marketing to mothers and free samples, which can undermine successful breastfeeding. But, the report says, "manufacturers are still flouting the code by heavily promoting manufactured baby milk and food".

A Guardian investigation in Bangladesh found widespread use of "prescription pads", where Nestlé reps give health workers tear-off pads, with pictures of their products, for them to pass on to mothers. Nestlé spokesman Robin Tickle said he did not believe the pads equated to promotion of the company's formula milks. The device was "a safety measure", to help mothers to be sure the milk they were buying was the right kind for their baby.